This page provides an independent statistical analysis and educational interpretation of publicly reported results. ClinicalTrials.gov provides the official trial registry record. Numerical trial results on this page are restricted to the results posted in the ClinicalTrials.gov record; calculations added by Clinical Biostats are labelled as such.
1. Trial at a Glance
This page covers the registry results for Myocardial Injury and Quality of Life After COVID-19 (NCT04794062), a registered phase not stated study. The primary outcome is Percentage of Patients (%) Recovered From COVID-19 With a Decrease in the Global Contractility of the Left and Right Ventricles..
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT04794062 |
| Phase | Phase not stated |
| Condition | COVID-19, Myocardial Injury, Myocarditis Post Infection |
| Allocation | Not Stated |
| Design model | Not Stated |
| Masking | Not Stated |
| Enrollment | 119 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Voronezh Regional Clinical Consultative and Diagnostic Center |
| Results posted | Yes |
2. Clinical Question
Population
Participants who recovered from pneumonia associated with COVID-19. The registry lists an enrollment of 119, but does not report the population for the primary outcome.
Intervention
There is no assigned intervention described. This is an observational study with follow-up and dynamic observation after recovery from COVID-19 pneumonia.
Comparator
No randomized or like-for-like control comparison is described. The registry does not state an allocation, and the adverse event record lists one group of recovered patients.
Primary question
During follow-up of up to 12 months, how many recovered participants have a decrease in global contractility of the left or right ventricle, as defined by sex-specific ejection-fraction thresholds?
The study’s stated purpose is early detection of myocardial injury and assessment of quality of life among people recovered from COVID-19. It also describes follow-up of selected participants with signs of myocarditis and/or myocardial fibrosis. These aims provide context for the primary endpoint, which counts participants meeting a ventricular ejection-fraction criterion.
The primary question is descriptive rather than a treatment-effect question: the registry does not specify an intervention whose effect is compared with a control. It also does not report a separate estimate of quality of life in the posted primary outcome information. The record therefore supports describing the planned clinical focus and the endpoint definition, but not judging whether recovery, myocardial injury, or quality of life changed by a particular amount.
3. Trial Design
The registry describes an observational study of participants recovered from pneumonia associated with COVID-19. Follow-up and dynamic observation were planned, with the stated goals of detecting myocardial injury and assessing quality of life. Selected participants with signs of myocarditis and/or myocardial fibrosis were to receive follow-up. The study is listed as completed.
The registry reports enrollment of 119. The study start date is 2020-09-16, and the primary completion date is 2021-10-01. The sponsor is Voronezh Regional Clinical Consultative and Diagnostic Center. These record details describe the study’s administrative scope; they do not establish how many participants contributed data to the primary endpoint or how many completed follow-up.
No randomized allocation or like-for-like control group is described. The registry does not state an allocation, and the adverse event information contains a single group labeled Patients Recovered From COVID-19. That group-level safety information should not be treated as evidence of a controlled comparison. The registry record does not report the timing or frequency of individual follow-up visits, the specific measurement procedures, or the criteria for selecting participants for additional follow-up.
The primary outcome is a participant count, expressed as a percentage, for decreased global contractility of the left or right ventricle. Its timeframe is up to 12 months. The record lists four outcome measures overall, but does not report the other outcome definitions in the registry record for this description. It lists no posted statistical analyses. Consequently, the study design and endpoint can be described, but no primary-outcome estimate or comparison can be interpreted from the registry record.
4. Participant Flow and Accounting
The registry reports how participants moved through each stage of the study. All counts below are exactly as posted; missing counts are not inferred from other stages.
Overall Study
| Stage | Patients Recovered From COVID-19 |
|---|---|
| STARTED | 119 |
| COMPLETED | 106 |
| NOT COMPLETED | 13 |
5. Baseline Characteristics
The table reproduces the baseline characteristics posted in the registry, which describe the participants analysed at baseline and help show whether the randomized groups were comparable.
| Characteristic | Unit | Patients Recovered From COVID-19 |
|---|---|---|
| Participants analysed | 106 | |
| Age, Continuous | years | 57.5 (49 to 64) |
| Sex: Female, Male: Female | Participants | 62 |
| Sex: Female, Male: Male | Participants | 44 |
| Race (NIH/OMB): American Indian or Alaska Native | Participants | 0 |
| Race (NIH/OMB): Asian | Participants | 0 |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | Participants | 0 |
| Race (NIH/OMB): Black or African American | Participants | 0 |
| Race (NIH/OMB): White | Participants | 106 |
| Race (NIH/OMB): More than one race | Participants | 0 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 0 |
| Region of Enrollment: Russia | participants | 106 |
6. Primary Endpoint
The registry lists the primary outcome as Percentage of Patients (%) Recovered From COVID-19 With a Decrease in the Global Contractility of the Left and Right Ventricles., measured over Up to 12 months.
| Element | Registry entry |
|---|---|
| Result type | Count Of Participants |
| Measure of spread | not applicable |
| Unit | Participants |
| Endpoint classification | Binary Endpoint |
The primary endpoint is the number, expressed as a percentage, of participants recovered from COVID-19 who meet a defined criterion for decreased global contractility of the left or right ventricle. The criterion is a left ventricular ejection fraction below 57% in men and women, or a right ventricular ejection fraction below 52% in men and 51% in women. The stated timeframe is up to 12 months.
Ejection fraction is a measure of the proportion of blood expelled from a ventricle with each contraction. As general statistical and clinical context, a threshold-based endpoint converts a continuous measurement into a count of participants who meet a prespecified category. This can make a clinical finding easier to describe as a participant frequency, but it does not preserve all the information in the underlying measurements. Participants close to either side of a threshold may be placed in different categories despite having similar measurements.
The endpoint is relevant to the study’s stated focus on detecting myocardial injury after recovery. However, the registry record does not report the observed count or percentage, the assessment details, or the result by ventricular chamber or sex. The endpoint definition alone therefore indicates what was to be counted, not how frequently the criterion was met.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry identifies a clear primary outcome definition, but it does not include a posted analysis result for that outcome. The primary outcome is a participant count, expressed as a percentage, of recovered participants meeting a ventricular ejection-fraction threshold during follow-up of up to 12 months. Without the observed count, denominator, or uncertainty interval, the frequency and precision of the finding cannot be assessed from this record.
The enrollment is 119, but that number should not be treated as the primary-outcome denominator. The registry record does not report how many participants had the measurements needed for the endpoint, whether all enrolled participants were followed, or how missing measurements were handled. It also does not provide a breakdown by left versus right ventricular criterion or by sex. Those details would matter for understanding the endpoint’s composition and the stability of any estimate.
The registry lists zero posted analyses. That means there is no reported primary-outcome estimate or inferential result to interpret in the available record. It is not possible to say from the record how many participants met the endpoint, whether the observed frequency was compatible with a particular reference value, or how precisely the frequency was estimated. No confidence interval or p-value for the primary outcome is reported in the registry record.
In general, a confidence interval describes a range of values compatible with the data under a statistical procedure and its assumptions. Its width conveys precision: a wider interval indicates greater uncertainty about the underlying value than a narrower one. Because no interval is reported for this endpoint, precision cannot be quantified. A p-value, when used, addresses compatibility of the data with a specified statistical null model; it does not by itself measure clinical importance or establish causation. No primary-outcome p-value is reported.
The observational design also limits causal interpretation. The primary endpoint describes a finding among people followed after recovery; it does not compare assigned treatments. Without a randomized or otherwise described comparison, any changes over time or differences between participant groups could not automatically be attributed to a particular cause. The registry does not report a specific causal analysis or adjustment strategy.
The adverse event record reports zero serious adverse events, zero other adverse events, and zero deaths among 106 participants at risk in the listed group. These counts are safety-record entries, not a substitute for the missing primary-outcome results. The distinction between 119 enrolled and 106 listed as at risk for adverse events is documented, but the reason for the difference is not reported in the registry record.
9. Statistical Methods Explained
What does a participant-count endpoint represent?
General explanation: a binary endpoint classifies each participant according to whether a defined event or criterion occurred. A count of participants meeting the criterion can be paired with a denominator to describe a proportion or percentage. This is different from analyzing a continuous measurement, such as ejection fraction itself, because categorization focuses on whether a threshold was crossed rather than how far a measurement lies from that threshold.
For this study, the primary outcome uses threshold criteria for left and right ventricular ejection fraction, with different right ventricular thresholds for men and women. The registry specifies that the result is to be expressed as a percentage of recovered participants. It does not report the observed count, the denominator used for the percentage, or how the two ventricular criteria are combined when a participant meets both. The result therefore cannot be reconstructed from the registry record.
Why does the endpoint definition matter?
General explanation: a threshold can make a result easier to communicate, but participants with measurements near a cutoff may be classified differently even when their measurements are similar. The chosen definition also determines which participants count as having the endpoint. For that reason, the threshold, assessment method, and handling of repeat measurements are important parts of interpretation. The threshold values are stated in the registry, but measurement procedures and repeat-measurement rules are not reported in the registry record.
What can an observational design establish?
General explanation: observational follow-up records outcomes without assigning participants to study treatments. It can describe what was observed in the followed group and how findings vary over time or across recorded characteristics, if those data and analyses are reported. By itself, an observational finding does not establish that an exposure or treatment caused an outcome. This record describes follow-up after recovery from COVID-19 pneumonia and does not describe randomized allocation or a like-for-like control group.
The stated purpose includes early detection of myocardial injury and assessment of quality of life. The record also mentions follow-up in selected participants with present signs of myocarditis and/or myocardial fibrosis. It does not report the selection criteria, visit schedule, or a statistical method for analyzing repeated observations. Without those details, the intended follow-up can be described, but its analytical implementation cannot be evaluated.
How should estimates and uncertainty be read?
General explanation: an estimate summarizes the observed data, while an uncertainty interval communicates how much imprecision remains under the chosen model and assumptions. For a binary outcome, the estimate would ordinarily depend on the number meeting the criterion and the number assessed. Sparse event counts can yield considerable uncertainty, and the method used to calculate an interval can matter. None of these primary-outcome quantities or methods is reported in the registry record.
A p-value is a measure of how compatible observed data are with a specified null model, under the assumptions of the analysis. It is not a measure of effect size, proof of no effect, or a direct statement of clinical importance. Since the registry lists no posted analyses, there is no primary-outcome p-value to interpret. The record also does not report a confidence interval or an adjusted estimate.
What do planning illustrations mean?
General explanation: sample-size planning asks how many participants may be needed to detect a specified effect under stated assumptions. Such calculations are prospective illustrations, not evidence about the result actually observed. The record’s planning assumptions describe a two-sided significance level of 0.05, equal allocation between two arms, a normal approximation, and an effect defined as a stated fraction of the observed effect. For time-to-event calculations, the assumption is that the displayed event total is the total number of events; other calculations are expressed as participants per arm.
Those assumptions do not turn this observational study into a randomized two-arm comparison. The record does not state an allocation or describe a like-for-like control comparison. The planning illustrations are therefore not observed power, and they should not be read as the study’s realized ability to detect a treatment effect. The registry does not report the rationale used to plan enrollment or a sample-size justification for the primary endpoint.
Why do missing methods matter?
General explanation: analysis populations specify which participants contribute to a result, and missing-data methods describe how unavailable measurements are handled. If participants with missing follow-up differ from those with measurements, a complete-case estimate may not represent the full enrolled population. The relevant denominator and missing-data approach are therefore needed to judge representativeness and precision. The registry record does not report the primary-outcome analysis population or missing-data method.
Likewise, prespecified analysis plans, multiplicity procedures, and any interim analyses can affect how results should be interpreted. These details are not reported in the registry record. Because there are no posted analyses, there is no reported set of outcome estimates against which to evaluate those methods.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists four outcome measures, but only the primary outcome definition is described in the registry record for this account. It does not report whether statistical testing was planned across multiple outcomes, whether any multiplicity adjustment was specified, or whether a hierarchy of outcomes was used. The record also lists no posted analyses. Accordingly, there is no reported family of p-values or estimates from which to assess the consequences of multiple testing.
Missing-data handling is not reported in the registry record. In particular, the record does not state how many participants had evaluable measurements for the primary endpoint, how participants without measurements were treated, or whether any imputation method was used. Enrollment of 119 does not identify the analysis population. The adverse event record lists 106 participants at risk, but that safety denominator should not be assumed to be the primary-outcome denominator.
Analysis populations are important because they define who contributes to each estimate. General explanation: if participants with missing follow-up differ in relevant ways from participants whose outcomes are measured, the resulting estimate may not describe all enrolled participants. The direction and extent of any such influence cannot be assessed without the number and pattern of missing measurements and the analysis method.
The registry record does not report interim analyses, an analysis plan, or the statistical approach used for the primary outcome. These omissions do not establish that such procedures were absent; they mean they are not reported in the registry record. With no posted analyses and no reported handling of missing data or multiplicity, the primary result’s analytic basis and precision cannot be evaluated.
11. Safety Results
The registry reports serious adverse events as affected participants divided by participants at risk.
| Arm | Participants with serious adverse events | Participants at risk | Percentage |
|---|---|---|---|
| Patients Recovered From COVID-19 | 0 | 106 | 0.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Patients Recovered From COVID-19 | 0 of 106 |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 5% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Patients Recovered From COVID-19 | 0 of 106 |
The registry’s adverse event information lists one group, Patients Recovered From COVID-19. In that group, 106 participants are listed as at risk, with zero serious adverse events, zero other adverse events, and zero deaths. No serious adverse event terms are listed.
These are counts recorded for the listed group; they do not establish that adverse events were impossible or that none occurred outside the recorded risk set. The record does not explain why the safety group contains 106 participants when overall enrollment is 119, nor does it report the method used to collect or classify events. It also does not provide event timing or participant-level detail.
General explanation: a zero count is interpreted in relation to the number of participants observed, the duration and completeness of observation, and the way events were collected. A zero count is not itself proof that the underlying event risk is zero. No uncertainty interval is reported for these safety counts. Because the study is observational and the record lists no comparator group, these figures do not support a comparative safety assessment between treatments.
12. What the Result Does, and Does Not, Mean
The registry record describes an observational follow-up study focused on myocardial injury and quality of life after recovery from COVID-19 pneumonia. Its primary endpoint is defined using left and right ventricular ejection-fraction thresholds, with a follow-up timeframe of up to 12 months. This gives a clear account of the clinical finding the study intended to count.
The record does not report the primary outcome’s observed count or percentage, and it lists no posted statistical analyses. As a result, the available information does not show how often participants met the endpoint, how precise an estimate was, or whether results differed by ventricular chamber or sex. It also does not provide a reported quality-of-life result. The endpoint definition should not be mistaken for an outcome finding.
The study is observational and no randomized allocation or like-for-like control comparison is described. The record therefore does not support a treatment-effect conclusion. General explanation: observational data can describe findings in the people followed, but causal claims require a design and analysis that address alternative explanations. Details of any such analysis are not reported in the registry record.
The safety record reports zero serious adverse events, zero other adverse events, and zero deaths among 106 participants at risk in the listed group. These entries describe the recorded safety counts; they do not resolve the missing primary-outcome result, and no comparison is available. The difference between the enrollment of 119 and the safety risk group of 106 is not explained in the registry record.
Overall, the record establishes the study’s stated population, follow-up purpose, endpoint definition, and selected administrative details. It does not establish the frequency or precision of the primary outcome, the change in quality of life, or a causal relationship between recovery and myocardial findings.
13. Why This Trial Matters Statistically
This study raises a statistical question that is easy to overlook: a clear endpoint definition is not the same as a reported result. The registry specifies ventricular ejection-fraction thresholds and a follow-up timeframe of up to 12 months, but it contains no posted analysis of how many participants met those criteria. Without the count and denominator, readers cannot evaluate either the estimated frequency or its precision.
The endpoint also illustrates the tradeoff involved in converting a continuous measurement into a binary classification. General explanation: a threshold-based outcome can be straightforward to communicate, but it discards information about the size of measurements and can make classification sensitive to values near the cutoff. The sex-specific right ventricular thresholds and the separate left ventricular threshold define the classification rule; the record does not provide the measurement procedures needed to assess how it was applied.
The observational design is another important statistical feature. The stated focus is follow-up after COVID-19 pneumonia, not a randomized comparison of assigned treatments. That distinction affects the questions the study can answer: a descriptive frequency in a followed group is not itself a causal treatment estimate. No comparative analysis is posted in the registry.
Finally, the difference between overall enrollment and the safety group’s number at risk illustrates why denominators need to be reported for each outcome. The record does not explain that difference, and the safety denominator should not be carried over to the primary outcome. Transparent analysis populations, missing-data methods, estimates, and uncertainty intervals would be needed to assess the primary finding statistically; those details are not reported in the registry record.
14. Limitations
- The posted summary statistics are the only data these results rest on; patient-level data, full protocols and statistical analysis plans are not available.
- Recalculated results are simple, unadjusted calculations from posted summaries. They do not replace the sponsor's prespecified analysis.
The most direct limitation for interpretation is that the registry record lists no posted statistical analyses. It therefore does not report the primary outcome’s count or percentage, an uncertainty interval, or a p-value. The primary endpoint is defined, but its observed frequency and precision cannot be assessed.
The enrollment is 119, while the adverse event group lists 106 participants at risk. The registry does not explain the difference. It also does not report the number of participants with evaluable primary-outcome measurements, the analysis population, or the handling of missing observations. The safety denominator cannot be assumed to be the primary-outcome denominator.
The record describes observational follow-up, without a stated allocation or a like-for-like control comparison. This limits the scope for causal interpretation. The registry does not report an adjustment strategy or a specific comparison analysis. Details of assessment methods, the timing and frequency of follow-up, and the selection criteria for participants with signs of myocarditis and/or myocardial fibrosis are also not reported in the registry record.
Although four outcome measures are listed, only the primary endpoint definition is described in the information. The record does not report a multiplicity approach, an interim-analysis plan, or the statistical analysis plan. It also does not report a separate quality-of-life result. These gaps mean that the study’s stated aims are broader than the results that can be interpreted from the registry record.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Myocardial Injury and Quality of Life After COVID-19 — NCT04794062.
- Registry record last updated 2024-11-19; status last verified 2024-11.
- Results first posted 2024-02-15.
- Data retrieved from ClinicalTrials.gov on 2026-11-09.
- Group sizes, means, event counts and sponsor-reported p-values are reproduced as posted. Effect estimates, confidence intervals and p-values not attributed to the sponsor are independently calculated from the posted summary statistics.
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18. Record Summary
The registry record describes a completed observational study of people recovered from COVID-19 pneumonia, with enrollment of 119 and follow-up focused on myocardial injury and quality of life. The study start date is 2020-09-16, and the primary completion date is 2021-10-01. The sponsor is Voronezh Regional Clinical Consultative and Diagnostic Center.
The primary outcome counts participants meeting left or right ventricular ejection-fraction thresholds during follow-up of up to 12 months. The registry lists four outcome measures and zero posted analyses. It does not report a primary-outcome result, its denominator, or a confidence interval. For the listed safety group, 106 participants are at risk, with zero serious adverse events, zero other adverse events, and zero deaths. The reason for the difference between enrollment and the safety group is not reported in the registry record.